Honda 400/4 Restoration

[mattb_uk]

Hi All,

This thread will hopefully be the story of the restoration of my Honda 400/4.

I dont really know where to start but I guess the reason I am doing this in the first place is because I have always been interested in all things mechanical and enjoyed tinkering on previous bikes but I have never had the guts / knowledge to just get stuck in and strip an engine/frame down and really get my hands dirty.

I often come on here and read all the project posts which are truely amazing/inspiring/knowledgable/funny etc. I guess the real thread that has inspired me to give it a go properly is Qwicktunes efforts with his GPZ, he said straight off that he was a novice but got stuck in, wasnt afraid to ask perhaps basic questions etc and that is exactly where I am at. I have done top end rebuilds on air cooled 125s in the past and taken engines in and out of my CB500 race bike, but the thought of going inside an engine, and doing a proper build had filled me with fear!

I bought the 400/4 because it was the first bike I ever sat on and have always wanted one. I have had bigger and faster road bikes, but i didnt want anything too fast as I get my speed fixes on the track and personally prefer to ride something you have to work at a little bit to go fast on the road. I had been looking for a while and good examples go for £2,000 up to £3,500 plus for an immaculate one. I wanted something I could ride for the summer and then rebuild over the winter. Eventually this one came up for £1800 on ebay with a decent enough looking history and condition. The previous owner said there was a rattle, which he suspected to be cam chain. I have done my research and this was a common problem with these bikes so it didnt put me off so I offered £1250 and he accepted. Sorted!

I collected the ike and the general condition was pretty good, no nasty surprises and the expensive things, downpipes, tank, mudguards etc all look in decent conditions with no major signs of corrosion etc. The engine had the rattle but again i had done my research and looks at the various ways of adjusting the cam chain as the adjusters can seize and wear apparently. I wasnt entirely surprised when all the stated methods didnt work, so have come to the conclussion that the adjuster has seized or the chain itself has become so slack that it has worn away at the pivot of the horseshoe adjuster (appologies, not sure of the right term but Im sure some of you will know what I mean) preventing it moving freely.

Therefore, I have come to the conclusion to do the rebuild now and just get stuck in, the only way to get over my fear of engine internals i figured was to stop worrying about it and just go for it, I figured there is masses of info on these bikes online and hopefully you knowledgable/kind/good good looking folks will offer some words of wisdom/encouragement/condolences etc to see me through, and hopefully keeping this record will give me some motivation to see it through to the end.

I realise threads like this are less interesting without pics so have taken pics of progress up until now.

Oh yes...I suppose the I should say what I am aqually tryign to acheive. ecause of the cam chain issue i want to replace the cam chain and adjusters etc. You can get split chains but I want to do it properly and fit a genuine closed chain and also to get to the 'horseshoe' adjuster I will need to split the cases and find out what a bottom end looks like! While I am doing all this I'd like to clean the engine up and get it sparkling again and when and if this is complete do the frame. Originally I wanted to ride the bike in the summer so I might just do the engine and ride the bike this summer and do the frame and bodywork etc over winter. This might change later on depending on how well its all going.

Right, onto the bit we all love, the pics.....

This is what I bought for my £1,250....Engine and luggage rack were the first things to go, I havent weighed them yet but the power/weight ratio must of dramatically improved since!

https://i1163.photobucket.com/albums/q560/mattb_uk/IMAG0755.jpg

https://i1163.photobucket.com/albums/q560/mattb_uk/IMAG0750.jpg

[mattb_uk]

I know everyone appreciates a good garage pic, so here is ours, its also where Ill be doing the strip/re-build....

https://i1163.photobucket.com/albums/q560/mattb_uk/IMAG0757.jpg

Furthest away is my CB500 race bike, then we have the 400/4, then my girlfriends NC30 and you can just see the mudguard of my XR400.

On with the strip down...

Tank off....so far so good, I can do this....
https://i1163.photobucket.com/albums/q560/mattb_uk/IMAG0787.jpg

Rocker cover off, all looks normal to me....
https://i1163.photobucket.com/albums/q560/mattb_uk/IMAG0789.jpg

I took the rocker cover off before taking the engine out because there was a method of adjusting the cam chain or at least diagnosing the what the fault was by taking the cover off and losening the two bolts on the adjuster arm and seeing if it jumps forward. Overall I came to the conclusion via some proding around that the chain was definately too lose and the the engine needed to come out and the full strip down begun....

Headers off...
https://i1163.photobucket.com/albums/q560/mattb_uk/IMAG0817.jpg

Carbs were a bugger to get off, then the engine came out....
https://i1163.photobucket.com/albums/q560/mattb_uk/IMAG0829.jpg

on the bench....
https://i1163.photobucket.com/albums/q560/mattb_uk/IMAG0826.jpg

I have since taken the head off (will post pics tomorrow) and am pretty much ready to start on the bottom end but am making sure I have enough containers etc for all the bits and to make sure I have plenty of time and information so Im not rushing it. Ill then start the no doubt expensive shopping list of things to replace.

Matt

[highland biker]

sweet

jealous of your garage
____________________
past: klx 250, cbr125, SRAD 600, cbr600rr
present: uber practial r1 for the daily commute

[mattb_uk]

As I said, here are the pics of where I am up to now....

Camshaft out, along with tensioner slipper guide, I thought it odd that the groves in the guide ran at a slight diagonal rather than prefectly vertical, is this normal?!....
https://i1163.photobucket.com/albums/q560/mattb_uk/IMAG0847.jpg

https://i1163.photobucket.com/albums/q560/mattb_uk/IMAG0846.jpg

Head off, piston crowns look a bit sooted up, does this mean it was running rich?....
https://i1163.photobucket.com/albums/q560/mattb_uk/IMAG0854.jpg

https://i1163.photobucket.com/albums/q560/mattb_uk/IMAG0856.jpg

I wasnt workign in great light but the bores looked good to me, if a little glazed, though like I said hard to tell in the light
https://i1163.photobucket.com/albums/q560/mattb_uk/IMAG0860.jpg

https://i1163.photobucket.com/albums/q560/mattb_uk/IMAG0861.jpg

And finally, where I am at now...
https://i1163.photobucket.com/albums/q560/mattb_uk/IMAG0862.jpg

I'd be really grateful if anyone who knows these bikes could just let me know what if anything I shoul dbe looking out for as i begin to strip it further.

Cheers,

Matt

[Oldgrumpy]

Nice bike, and a bargain price you got it for.

Re replacing the camchain - would you not consider splitting the chain and put in a soft link ?pretty sure David Silver stocks them - save you a lot of work. Did my self on a CB550 years ago and never had any problems. I remember a guy called Tony Galea back in the 1980's who was a mobile cam chain replacement service who did just that for a living - and very successfully too! Save you splitting the crankcases.

One thing to look out for - the oil feed bars for the cam - make sure they're scrupulously clean - the cam runs directly in the head and they have been known to clog up and wreck the cylinder head.

Another sod is the centre stand pivot sleeve - renowned for seizing up.

Ive got a Haynes Manual for this model in my collection so if you want any particular info give me a shout and I can sernd you a copy.

Good luck.


EDIT Can't believe it, the guy is still going https://www.galeacamchainservices.co.uk/services.html.
____________________
Fuel injection? Nah - carburretors - It's the way ahead - an condensers, points ......drones on

[alun111]

Good work so far.

When splitting the cases you want to be taking EVERYTHING off, There are sometimes hidden bolts you see. Otherwise you'll be wondering why the bugger won't split.

I don't mean to be patronising when I say this, but, have you dropped the oil yet? You'll make a right mess otherwise!
____________________
Summer: '00 Honda CB600F Hornet
Winter: '93 Suzuki GSF 400 Bandit VP Variable Valve
Past Bikes: Lifan LF100-5 Lifan LF125-A Honda C70

[mattb_uk]

[mattb_uk]

[Sako]

will be keeping an eye on this thread, love the projects threads!

[mattb_uk]

Could anyone possibly recommend the best way of cleaning up the carbon deposits on the piston crowns and valves and just generally removing all the grime?

Or is it best just to get it all vapour blasted? IS that the best option of the blasting methods?!

Apologies for the novice questions, but thats basically what I am !

Any suggestions more than welcome

Matt

[Oldgrumpy]

Caustic soda - just make sure you don't use it on aluminium.

I used to use it for decoking 2 stroke exhausts - bunged up the end filled them up and left them overnight - and poured the shit down the drain afterwards - the good old days before the word "environment"was invented lol.

Be careful not to inhale the solution when mixing - it's vile stuff.
____________________
Fuel injection? Nah - carburretors - It's the way ahead - an condensers, points ......drones on

[nisp]

Should add you mix caustic soda to water not the other way around.
____________________
Suzuki TS 50 1999 Honda CB 125 t2 1981 Yamaha XJ 600 s Diversion Honda cx 500 MZ ETZ 250 1985 Yamaha FZR 400 1981 Suzuki TS 185 1984 Triumph bonneville 790 2001 MZ TS250 1979 Suzuki sv 650 1999 KTM exc RFS 450 2007 Hercules mx 125 1976

[mattb_uk]

Thanks for the tip, Ill look into it.

Was away this weekend so didnt get to do any more but should be gettign some more done this week.

Matt

[mattb_uk]

Its bene a while but I have been chippign away at it as and when I have had a few moments....

Barrells off
https://i1163.photobucket.com/albums/q560/mattb_uk/IMAG0861.jpg

And pistons off...
https://i1163.photobucket.com/albums/q560/mattb_uk/IMAG0888.jpg

Fly wheel off next, though a bit worried the puller damaged the flywheel, i didnt realise they were so soft?....
https://i1163.photobucket.com/albums/q560/mattb_uk/IMAG0891.jpg

I assume this isnt enough damge to cause a detrimental effect to the running of the bike....
https://i1163.photobucket.com/albums/q560/mattb_uk/IMAG0916.jpg

[mattb_uk]

Right, come up against a bit of a problem here....

For the life of me I can't get the castle nut off the clutch hub, the manual says you can get it off without the castle socket so i tried that and nothing, I didnt want to damage it too much so I waited and got myself the proper castle socket to fit. Nothing, it wont even budge a fraction, tried an impact drive too, nothing still.

Am I doing somethign wrong? Initially the hub just spins unless you engage the clutch, which I cna only seem to do by forcing the plates togeter with a screwdriver!

Am I making a really obvious amateurs mistake here or am I missing something?!

https://i1163.photobucket.com/albums/q560/mattb_uk/IMAG0924.jpg

Any suggestions would be welcome!!

[Hetzer]

Doesn't that nut undo clock-wise?
____________________
"There's the horizon! Ride hard, ride fast and cut down all who stand in your way!"

[garth]

As above, could be a spastic thread.

[mattb_uk]

I did actually think that, and tried it briefly, maybe i had already overtigtened it. Ill see If I can find some info online somewhere!

[mattb_uk]

Checked the old Honda manuals for the bike and parts diagram, nothing mentions it being a reverse thread, which I would of thought it would?

[Suntan Sid]

[Oldgrumpy]

[Suntan Sid]

[Oldgrumpy]

[mattb_uk]

Right, apologies accepted, back on track....

I have finally got the nut off, felt like I'd won the lottery!

Engine is all stripped now, will post some photos later.

Felt justified in the decision to strip it right down now as the cam chain adjuster was well work and the pivot wasn't pivoting any more.

Fingers crossed I can get it all back together!!